Not Applicable.
Not Applicable.
During the fabrication of semiconductor devices it becomes necessary to remove various materials from a substrate. Increasingly, plasma etching, reactive ion etching, ion milling and the like are used as the means of removing material from a substrate. During these removal processes various by-products are formed. These by-products are formed from the interaction of various combinations of plasma gasses, substrate and resist materials. The by-product formation is also influenced by the type of etching equipment and process conditions. For purposes of this invention all the various by-products will be collectively referred to as etch residue. In addition to being redeposited on a substrate etch residues tend to form unwanted deposits on the exposed surfaces of the etching equipment. In an effort to extend the useful life of etching equipment various methods have been proposed for removing the unwanted deposits from the surface of exposed parts of the etching equipment. An example of a method for removing the unwanted residues from etcher parts consists of blasting the surface of the part with small particles such as sand or glass microspheres. Other methods require dipping the etcher parts in a bath. An example of this method is disclosed in U.S. Pat. No. 5,334,332. According to the ""332 patent the etcher parts are dipped in a bath comprised of hydroxylamine, an alkanolamine, water and catechol.
The present invention is directed to a method of removing etch residue from etching equipment without damaging the surface of the equipment. The compositions used in the method of the invention are aqueous and free of hydroxyl amine. The aqueous compositions are comprised of an acidic buffer solution, a polar organic solvent that is miscible in all proportions in water, and a fluoride. The compositions have a pH of from about 3 to about 6.
Not Applicable.